Error trying to strip changeset from repository

One of our dev team incorrectly pushed his wrong local repo into one of our bitbucket repos (202 changesets affected). I successfully stripped the pushed changesets from 2 local repos for users who pulled from the affected repo on bitbucket. However, when I try to strip the changeset from bitbucket I get 'an error has occurred ...'

The affected repo is 'iFiOld' and the changeset I am trying to stip is 423b4b6012f1